In an age of austerity and public service cuts, Britain's trade union leaders are playing a more central role than for many years. In the run-up to the TUC congress, Elizabeth Day and Euan Ferguson get to know them better

More than 90,000 civil servants at the Department of Work and Pensions are set to take strike action in protest over job cuts, Mark Serwotka, general secretary of the Public and Commercial Union, said today.